Multi-user Multi-Channel (MU-MC) communication that allows multiple terminals to use multiple channels simultaneously has become a focus of attention. This communication is also called a channel-based OFDMA (Orthogonal Frequency Division Multiple Access) communication. For example, methods of simultaneously transmitting data from a transmitting terminal (base station or the like) to multiple receiving terminals using multiple channels other than the primary channel have been discussed.
The MU-MC communication uses the multiple channels. It can thus be considered that during the base station's transmission to a terminal through a certain channel, another terminal starts transmission to a terminal through another channel to the base station. In this case, to allow the base station to receive the signal through the other channel concerned, a full duplex scheme is required to be supported. This requirement complicates the configuration of the base station. In a case where the base station does not support the full duplex scheme, the base station can receive no signal. Consequently, the terminal uselessly consumes power.